1 #define SDA_IN()  {GPIOB->CRH&=0XFFFF0FFF;GPIOB->CRH|=8<<12;}
2 #define SDA_OUT() {GPIOB->CRH&=0XFFFF0FFF;GPIOB->CRH|=3<<12;}
3
4
5 #define IIC_SCL    PBout(10) //SCL
6 #define IIC_SDA    PBout(11) //SDA
7 #define READ_SDA   PBin(11)  //ÊäÈëSDA 

 1 u8 ds1307_Read(u8 ReadAddr)
 2 {
 3         u8 temp,dat;
 4         int k;
 5         IIC_Start();
 6         IIC_Send_Byte(0xd0);
 7         IIC_Send_Byte(ReadAddr);
 8         IIC_Stop();                      //这里一定要重启IIC总线，否则会读错误
 9
10         IIC_Start();
11         IIC_Send_Byte(0xd1);
12         if (IIC_Wait_Ack())
13                 return 0xff;
14
15     temp = IIC_Read_Byte();
16     IIC_NAck();
17     IIC_Stop();
18
19         return temp;
20 }

 1 u8 IIC_Read_Byte()
 2 {
 3         unsigned char i,receive=0;
 4         SDA_IN();
 5     for(i=0;i<7;i++)        //这里修改为7次，不然秒时针会一次递增2个单位
 6         {
 7       IIC_SCL=0;
 8       delay_us(2);
 9             IIC_SCL=1;
10       receive = receive<<1;
11       if(READ_SDA){
12                 receive++;
13             }
14             delay_us(1);
15     }
16     return (receive);
17 }

 1 void ds1307_Write(u8 WriteAddr,u8 Data)
 2 {
 3     u8 temp;
 4
 5     temp=(Data/10*16)+(Data%10); //16进制转BCD
 6
 7     IIC_Start();
 8     IIC_Send_Byte(0xd0);                9     //IIC_Wait_Ack();
10     IIC_Send_Byte(WriteAddr);        11     //IIC_Wait_Ack();
12     IIC_Send_Byte(temp);            13     //IIC_Wait_Ack();
14     IIC_Stop();
15     delay_us(10);
16
17 }

 1 u8 IIC_Send_Byte(u8 txd)
 2 {
 3     u8 t;
 4         SDA_OUT();
 5     for(t=0;t<8;t++)
 6     {
 7             if((txd&0x80)>>7)
 8                 IIC_SDA=1;
 9             else
10                 IIC_SDA=0;
11             txd<<=1;
12             delay_us(2);
13             IIC_SCL=1;
14             delay_us(4);
15             IIC_SCL=0;
16     }
17
18
19         SDA_IN();
20         delay_us(4);
21         IIC_SDA=1;
22         //delay_us(2);
23         IIC_SCL=1;
24         delay_us(2);
25         if (READ_SDA==1)
26         {
27             IIC_SCL=0;
28             return 1;
29         }
30         else
31         {
32             IIC_SCL=0;
33             return 0;
34         }
35 }